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25

This is going to get a bit technical but should still be understandable even if you slept through chemistry classes. When is hydrogen dangerous? Just as with the fuel-air mixture in an engine, hydrogen is combustible only when it's within a range of concentrations. We use what are called the Lower Explosive Limit (LEL) and the Upper Explosive Limit (UEL) ...


19

The battery is toast. Save yourself potential serious injury. Buy a new one. If the battery has been dead for eight months...it is pretty much a goner.


17

Use the jumper battery to start the engine, then disconnect it and leave the engine running (with no current drain such as lights, heater fan, radio, etc). The car should charge its own battery to 80% charge in about two hours (assuming the battery and alternator are in good condition; the battery may be damaged by being uncharged for so long, but I've never ...


16

The reason I would connect the positive cable first (in a negatively-earthed car) is that while tightening the positive connector with a spanner (wrench), if I were to touch the body of the car with the spanner at the same time, nothing would happen and I would be OK. However if the negative was already connected to the battery and I shorted the positive to ...


14

Sure you could put a bigger battery in .What may happen is that the total proposed draw is too much for the dynamo and it will go flat.Even if it does not go flat because your appliance usage patterns are intermittent you will get a lower battery life because of the constant cycling .If dealing with the charging system is too hard or too expensive then ...


13

You don't need to solder them, clean the terminals really well and apply some dielctric grease or buy some battery terminal protector, this is a spray that you can spray on the terminals and this will keep the battery form corroding. I personally use heavy duty bearing grease to apply over and around the terminals, this helps really well keeping the ...


13

Your question is difficult to answer without you knowing the inner workings of an alternator. The basics. If you move a magnetic field near a coil of wire the electrons in the wire get exited and electricity will be made. The amount of electricity made depends on the size of the magnetic field and its speed. The bigger the field and the faster it's moving ...


12

tl dr: Corrosion (once cleaned) is not a huge issue. It is just typical corrosion on the battery terminal. See this image: (NOTE: This is a 6V battery, but the same principles apply.) The blueish color you see is hydrated copper sulfate. When acid vapors escape from the battery, it can cause a reaction with any copper which may be in the terminal. The ...


12

Lead acid type batteries, such as this, like to be charged very slowly. Under 5 amps for many hours would be best. During fast charging the internals overheat and electrolyte can boil. Best to charge slowly if time allows. This type battery has its worst damage happen when it is stored discharged. The chemistry in this state is more acidic. This acid ...


12

I can't give you numbers or calculations without some work, but I can tell you than energy is never free. Cars have an A/C compressor that is mechanically driven by the engine because this is the easiest way to get the job done in a typical consumer car. An A/C compressor actually takes a huge amount of energy to operate. In fact a central A/C unit for a ...


11

I am no expert in this topic, but I don't think a "cloud of gas" forms around the battery. Hydrogen gas is the lightest gas of them all (0.089 g/l) and won't pool up if leaked. It will simply rise as long as the bonnet is open because it is less dense than air, which is mostly much heavier nitrogen (1.25 g/l) and oxygen (1.4285 g/l). My guess is that the ...


10

The starter circuit should only draw whatever current it needs so the excess shouldn't cause any problem.


10

IIRC, the Prius has a step down voltage regulator which charges the 12v battery from the main power. I'd bet this system is having an issue and is not charging the battery. As for the 12v battery. I'd bet the old battery (the first replacement?) is good, but has dropped in voltage below what the charger can deal with. To overcome this, you need a second ...


10

This battery pack is rated for 4A at 12V. But a really empty car battery can easily draw much more that 5A when connected to 12V, which is definitely too much for your battery pack. The LiPo battery itself can deliver lots of, but not unlimited current. At high currents, it can get really hot and even start a fire. The battery pack contains a protection ...


9

The two biggest disadvantage of lead acid batteries compared to the newer types like Li Ion are that they are heavier, and that they contain liquid acid. Another possible issue is that they can produce hydrogen gas. On the other hand, they are very inexpensive, have a long life expectancy, have a very high tolerance for overcharging without being damaged, ...


9

Since you have a battery which isn't that old (most batteries have about a five year life span), I'd suggest you put it on a charger and try to recharge it. This will allow the battery to come back to full charge without putting an undue stress on your alternator. You have to decide if the time spent in recharging the battery is worth your time. To me, ...


9

Yes its possible to start a car with Ultra capacitors. These caps don't appear to have a cycle life that the traditional lead acid batteries have. The ability of these caps to provide starting current is very good. There are a couple of snags: The caps at present are more pricey than the best lead acid batteries. The caps are strung in series to get the ...


9

As long as it is not overcharging your battery, it will increase the useful life of the battery. The reason behind this is, as a battery sits, it loses power. Some of the electrolysis which goes on to make a battery work, also breaks down the battery. During this period, the battery goes through a sulfating period, where sulfur crystals grow on the lead ...


9

A @FredWilson says, you need to charge it slowly - either by driving it around or by using a trickle charger. If you can get a trickle charger with a 'maintenance mode', you can leave it permanently attached to the car and it will keep the battery topped up and stop it going flat in the first place. If possible, I'd also recommend finding someone you trust ...


9

Well, Teslas (and presumably other all-electric cars) have A/C so it's not impossible, but A/C takes a fair amount of power. On the other hand, Teslas store a lot of energy. The A/C is something like 2.4kW which is about 8,000 BTU/h or about 3HP. So using an electric motor on a conventional car might give you a few more HP briefly, but the alternator has ...


9

This shouldn't be too crazy. You will probably need a multimeter to test things. (If you watch the specials carefully, there is at least one tool outlet that gives these away as special coupon deals I would start the journey with the service manual. It's available here. Check out section #6, electrical. Your system is pretty simple. A couple of ...


8

Gloves are not essential, but highly recommended When replacing a car battery there are three potential hazards that relate to safety: electrical hazard - the battery is capable of generating 100's of amps' worth of current. You want to avoid shorting the two terminals with something like a wrench, cable or hand jewellery. In this regard, gloves can help ...


8

The Voltage levels let you know how much charge is present in the battery thus warning you before the entire thing drains out. For example the below information is for the standard car battery which starts the car, works the steoreo etc , not the additional equipments like on the ambulance. 12.66v . . . 100% Charge 12.45v . . . 75% 12.24v . . . 50% ...


8

I think you have an issue with the way you are thinking. You are describing the issue as if the batteries are hooked up in series. In that case, yes there'd be a huge back current going on. Both batteries would be made into a complete circuit and you'd have global thermal nuclear meltdown (or whatever the car battery equivalent would be). This is not the ...


8

Yes, as everyone is stating, a spark igniting hydrogen gas could cause an explosion, causing injury from small parts, sulfuric acid or both. Very nasty. Hydrogen gas is a byproduct of electrical energy created from a chemical reaction of lead plates submerged into the acid and water. Sparks can happen internally, too. Like when the lead plates warp from ...


8

Repeated clicking is a result of not enough power making it to the starter. Your battery either has a bad connection, or is too weak to turn the starter motor. Battery Connection Your problem may be entirely due to a bad connection. Starters draw a lot of amps, and batteries are weaker in cold temperatures. I'd start by fully exposing the terminals. You ...


8

A battery that has an internal electrical short, usually one of the plates has come loose and is touching its neighboring plate will cause the alternator to work much harder than normal. This can shorten the life of the alternator. This condition is usually discovered quickly as the battery will not function well in this case. When alternators or motors ...


8

The short answer to your question is no. As @JPhi1618 noted, the compressor is mechanically driven. Without the compressor you don't have any cooling. The AC runs by changing the state and pressure of a liquid, and compressing the liquid is a big part of that cycle. If you bolted an electric compressor onto the car you would have to find a way to switch ...


7

The amp count tells you the maximum amount of current that the equipment can supply. Eg. Your car needs 600 amps to start: The 1000 amp jumper can handle it. Your car needs 1200 amps: The 1000 amp jumper can't do it. You'll have to find a bigger one. Be aware that this does not apply to voltage. If you have a 6V battery and you connect it to a 12V ...



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